Know your food!

Rendezvous with a scientist- Dr. Christiani Jeyakumar Henry
Rendezvous with a scientist- Dr. Christiani Jeyakumar Henry

Dr. Christiani Jeyakumar Henry
Lead, Nutritional Sciences and Human Physiology
Director, Clinical Nutritional Research Centre, Singapore Institute for Clinical Sciences, A*STAR
Professor, Department of Biochemistry, Yong Loo Lin School of Medicine, NUS

Professor Christiani Jeyakumar Henry initially trained as a Food scientist and subsequently obtained his MSc and PhD in Nutrition from the London School of Hygiene and Tropical Medicine. In June 2011 he was appointed as Director of Clinical Nutrition at Singapore Institute of clinical Science to spearhead the translation of Nutrition research into food applications.

We met with Professor Henry and talked to him about CNRC and its efforts to research on nutrition and understand, in general, about food and its consequences in the modern era. This rendezvous piece is a dialogue between Professor Henry and me (Laxmi Sankaran).

Your institute, Clinical Nutrition Research Centre (CNRC) is relatively new. What kind of research do you do there?

The official launch of CNRC was in January 2014, though it was launched at the end of 2012. Despite its recent origin, we have made inroads into basic and applied nutrition research, significantly focusing on the needs of nutrition within the Asian phenotype. Asians respond to food and drugs differently and that is what sets us apart from other institutions. We are moving ahead in full force and it has been a good start so far.

There was a recent finding from your centre which talked about eating methods affecting the glycemic response in healthy adults. Could you please elaborate?

Yes, this is something which I conjured up while sitting in the Kopitiams of Singapore. Due to the multi-ethnic population here, I noticed that different adults had different means of eating rice here: Chopsticks (Chinese), spoons or with hands (Malays and Indians). I wanted to find out how the rate of ingesting rice affects glucose response.

So, glucose response or glycemic index (GI) measures the extent to which a carbohydrate-containing food raises blood glucose. It is compared to a reference food which is either pure glucose or white bread. So, foods in which carbohydrates could be easily digested and absorbed generally have a high GI and the sharpest increase in blood sugar after they are eaten. While, slowly or incompletely digested carbohydrates have a low GI, with a lower increase in blood sugar after eating.

Our study showed that if you eat rice with chopsticks rather than spoon or hand, your glycemic response is quite low mainly because the amount of rice which you can pickup with a chopstick is quite small and therefore the feeding frequency is buffered.

So you mean, when the same amount of rice was eaten by chopsticks, or spoons or by hand, the glycemic response varied?

Yes, that is the beauty of the study. Simply by altering the way you consume rice, you can alter the rate of carbohydrate consumption. Of course, this doesn’t mean we are advising everyone to eat with chopsticks, but it tells you that if you eat smaller portions of rice, it can go a great way in reducing your carbohydrate intake. Also, if you eat slowly, you tend to feel full faster. Again, all this comes down to the way we eat; we as a society do not take time to eat our food. When I was in England, we used to have a sandwich, and we were done with lunch in 7 minutes. But in France, people take time out and go for lunch for an hour or so and enjoy their meal with a glass of wine. So, there is a cultural aspect of food consumption too which is equally important, but in general, in our rat race, we spend less time on how to eat, rather than what to eat.

Your institution is also measuring GI of certain selected popular foods consumed in South-East Asia. Could you shed some light on it?

Yes, we are systematically measuring the glycemic index of various popular local foods. This would help us have a repertoire of foods that you can look up in a booklet and make conscious decisions. This paper is still under press, but I can share some representative figures here.

Source: GI Research Unit at Temasek Polytechnic, HPB
Source: GI Research Unit at Temasek Polytechnic, HPB

Dishes like Bee hoon and our favorites, curry puff have a low GI (around 50) which is good news (laughs) but pink rice cake as you can see, has a very high GI (97). This is an example of applying good science to practical uses. This is especially important these days when diabetes and pre-diabetes is big in this part of the world.

Since majority of Singaporeans resort to Kopitiam food for their daily nutrition, we would like to know if it is healthy?

Well, everything in moderation is ok. In Singapore, the quality of food available in Kopitiams is of hygienic quality and also relatively cheap. You may be surprised that to prepare the same meal in your home, may be much more expensive. So, if your question is, is it healthy to eat continuously in a singular institution? The answer is obviously ‘No’. Eating in Kopitiams is fine, but perhaps, one could consider cooking their own food once in a while.

There have been several reports about high arsenic content in brown rice…

Most of the rice which used to be imported from all parts of Asia comes from regions which have got arsenic in their rice bowls. But in Singapore this is not an issue, because there is a close scrutiny of what is imported here and it is very well controlled by Agri-Foods and Vertinery Authority (AVA) of Singapore.

Red meat has been under scrutiny recently, is it good for health?

Again, it’s all about moderation. However, there is mounting evidence that eating a pure vegetarian, especially vegan diet, may not optimize the height growth in growing children. In other words, if you don’t consume milk or milk products, or don’t eat eggs, or fish or red meat, then it may not optimize their linear height growth.

Coming to diabetes and obesity, could you give me some statistics about its prevalence in Singapore and the situation in Asia in general?

About 11.3% of the population (aged 18-69years) in Singapore, are affected by diabetes while about 10.8% of the populace is predisposed to obesity. The highest prevalence is amongst Malays, followed by Indians and then Chinese. Malays and Indians show a high predisposition to Type 2 diabetes. And I personally feel, India and China are going to be the biggest challenges for us in terms of diabetes and obesity. It’s a national issue, but the two super giants haven’t invested enough on nutrition studies and it is a cause of concern.

Does late night binging contribute to obesity? Also, is consuming alcohol, related to obesity in the long run?

The whole question of circadian rhythm of eating is still kind of an open area but eating late certainly has some disadvantages. Firstly, the fact that you eat late, means you sleep immediately, which means your metabolic rate is slowed down considerably during sleeping, causing extra calories to be stored as fat. Secondly, it could predispose you to gastric refluxes. So, amidst the hustle and bustle of everyday life, I think it is important that people eat at a sensible time. You could probably have a high tea at 5-6pm in the evening and when you come back home, eat a smaller snack or fruit.

Alcohol, also needs to be had in moderation. In fact every single study, says that having a glass of red wine improves the quality of life and may better your health than not.

What is the kind of diet you would suggest for diabetic persons?

Three important things:

– Try and select low glycemic index foods.

– Have plenty of lentils and legumes, fruits and vegetables, and diary products.

– Reduce your rice consumption. Especially reduce the pace of eating rice and try to include yoghurt as a part and parcel of your meal, as it is a major contributor in lowering your glycemic index.

One of the major misconceptions around the world is that, when you are diabetic, you must cut down on all the sugar. The problem is people cut down on sugar, drink tea without milk, have tea without sugar etc. but eat lots of rice. So as an Asian, who has empathy towards these issues, this is a big challenge for me. How to get people to eat sensibly? This is where we are trying to improve the quality of your life with our application-based research. In a study of ours, we have shown that by combining foods, we can lower the glycemic index. For example, the glycemic response to white rice with chicken breast, ground nut oil and vegetables (GI-50) was significantly lower than consuming white rice alone (GI- 96). Thus, a balanced diet is always advisable.

 In conclusion, as a Nutritionist, what advice would you give our readers, so that we can maintain a healthy lifestyle.

I think the most important thing is that people should take some time off and enjoy the food they are eating. There is little sense in trying to do all that you do, if you have bad health. Devote some time to exercise everyday. Also do not feel guilty, if you have the indulgent chocolate once in a while! If you want to have a piece of chocolate, have a small piece, not the whole bar. Remember, prescription is a bad proscription. By telling people not to eat something, you set up a desire in their mind for it. Eat plenty of fruits and vegetables and think about your glycemic response when you eat, especially if you are an Asian. Drink plenty of things such as soya milk which is good in terms of glycemic response too. And if you can manage it, have a bowl of the miracle food like oats in the morning! Every single publication around the world has shown the good benefits of eating oats, as it improves your longevity and health outcome.